全文获取类型
收费全文 | 6410篇 |
免费 | 305篇 |
国内免费 | 64篇 |
专业分类
管理学 | 416篇 |
劳动科学 | 26篇 |
民族学 | 156篇 |
人才学 | 4篇 |
人口学 | 85篇 |
丛书文集 | 1552篇 |
理论方法论 | 315篇 |
综合类 | 3397篇 |
社会学 | 321篇 |
统计学 | 507篇 |
出版年
2024年 | 11篇 |
2023年 | 37篇 |
2022年 | 103篇 |
2021年 | 123篇 |
2020年 | 95篇 |
2019年 | 100篇 |
2018年 | 115篇 |
2017年 | 147篇 |
2016年 | 115篇 |
2015年 | 212篇 |
2014年 | 245篇 |
2013年 | 355篇 |
2012年 | 333篇 |
2011年 | 458篇 |
2010年 | 468篇 |
2009年 | 463篇 |
2008年 | 475篇 |
2007年 | 452篇 |
2006年 | 484篇 |
2005年 | 402篇 |
2004年 | 225篇 |
2003年 | 231篇 |
2002年 | 222篇 |
2001年 | 190篇 |
2000年 | 138篇 |
1999年 | 118篇 |
1998年 | 71篇 |
1997年 | 66篇 |
1996年 | 61篇 |
1995年 | 56篇 |
1994年 | 36篇 |
1993年 | 43篇 |
1992年 | 29篇 |
1991年 | 19篇 |
1990年 | 25篇 |
1989年 | 18篇 |
1988年 | 11篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1980年 | 1篇 |
排序方式: 共有6779条查询结果,搜索用时 31 毫秒
141.
通过发行"教育券"来解决流动儿童的入学问题是当前一种较流行的主张。但这一主张只是从表面上使中央政府、地方政府和流动人口家庭之间达成了一定程度的妥协,能够在一定程度上缓解流动儿童的入学难题,却无法触及到问题的根源,无法从根本上解决流动儿童的义务教育问题。其根源在于对弗里德曼教育券理论的一种错误理解和运用。在美国,教育券要解决的是促使不同类型的学校尤其是私立学校通过竞争得到发展的问题,而不是要解决谁应该为学生的义务教育买单的问题。只有将义务教育经费划拨从"以县为主"上升为"以省为主",才有望从根本上解决流动儿童接受义务教育的经费问题。 相似文献
142.
根据《波谱分析》课程的特点和教学实践经验,运用现代化教育技术、ChemOffice软件辅助等手段对该课程的教学方法进行了一些探索. 相似文献
143.
"90后"一代正处于15-24岁的青少年时期,是社会主义核心价值观培育与践行的重要人群。对上海、武汉和天津三地"90后"青少年的诚信观与友善观进行问卷调查结果表明,青少年对"友善"的认同显著高于对"诚信"的认同;随年级升高,诚信观趋向消极;女生对"诚信"和"友善"的认同均高于男生。家庭物质经济条件、生活安全感、亲子关系、同学关系、上网时间及青少年自我评价等对于社会主义核心价值观的认同影响显著。 相似文献
144.
Marjolein J. E. Greuter Xiang‐Ming Xu Jie‐Bin Lew Evelien Dekker Ernst J. Kuipers Karen Canfell Gerrit A. Meijer Veerle M. H. Coupé 《Risk analysis》2014,34(5):889-910
Several colorectal cancer (CRC) screening models have been developed describing the progression of adenomas to CRC. Currently, there is increasing evidence that serrated lesions can also develop into CRC. It is not clear whether screening tests have the same test characteristics for serrated lesions as for adenomas, but lower sensitivities have been suggested. Models that ignore this type of colorectal lesions may provide overly optimistic predictions of the screen‐induced reduction in CRC incidence. To address this issue, we have developed the Adenoma and Serrated pathway to Colorectal CAncer (ASCCA) model that includes the adenoma‐carcinoma pathway and the serrated pathway to CRC as well as characteristics of colorectal lesions. The model structure and the calibration procedure are described in detail. Calibration resulted in 19 parameter sets for the adenoma‐carcinoma pathway and 13 for the serrated pathway that match the age‐ and sex‐specific adenoma and serrated lesion prevalence in the COlonoscopy versus COlonography Screening (COCOS) trial, Dutch CRC incidence and mortality rates, and a number of other intermediate outcomes concerning characteristics of colorectal lesions. As an example, we simulated outcomes for a biennial fecal immunochemical test screening program and a hypothetical one‐time colonoscopy screening program. Inclusion of the serrated pathway influenced the predicted effectiveness of screening when serrated lesions are associated with lower screening test sensitivity or when they are not removed. To our knowledge, this is the first model that explicitly includes the serrated pathway and characteristics of colorectal lesions. It is suitable for the evaluation of the (cost)effectiveness of potential screening strategies for CRC. 相似文献
145.
一项项民间技艺如一颗颗美丽的珍珠,散落在乡野间的每个角落,经过岁月的打磨,散发出温润的光泽.而作为非遗工作者,就是那些采撷珠宝的人,要将它们一一串联,使其绽放更为动人的夺目光彩.2013年的初夏,我和同事们来到朝阳,找寻那颗遗留在深山里的珍珠——朝阳民间刺绣. 相似文献
146.
本文围绕城镇家庭户自然增长、城镇家庭户机械增长和城镇存量住房拆除三项需求来源,设计了基于人口普查等公开统计数据定量测算城镇新增住房需求规模的系统性方法,对2001—2010年和2011—2015年间全国和各省份城镇新增住房需求规模进行测算与分析。在此期间新增住房供需关系经历了从基本均衡向供过于求的变化,同时存量住房拆除引致的被动需求取代城镇家庭户自然增长和机械增长引致的主动需求,成为新增住房需求的最主要来源。东、中、西部省份在新增需求规模、新增供需比、需求结构等方面表现出明显差异。本文还进一步对2021—2030年的发展趋 势进行了定量预测。由于三项需求来源均趋于下降,2021—2025年和2026—2030年间全国年均城镇新增住房需求规模预计将较2011—2015年间分别下降33%和53%。本文设计的城镇新增住房需求规模测算方法和预测思路能够为各级政府“十四五”住房发展规划编制、房地产企业战略制定等提供参考。 相似文献
147.
信息化建设是医联体建设的重要内容和重点领域。现阶段的医联体信息化建设存在着医疗信息数据难共享、医疗隐私数据易泄露、医疗数据质量难改观等问题。文章通过梳理区块链的技术原理,发现区块链技术同医联体信息化建设有着高度的契合性并能以智能化的应对方式密切医患互动关系、保障数据高效共享、加强数据安全治理以及提升数据准确性、一致性、时效性和规整性,因此,区块链技术嵌入医联体信息化建设具有可行性。但区块链技术应用于医联体信息化建设在技术、理念、监管等方面还存在诸多挑战,未来仍需提升技术应用手段、转变医方观念体系、健全法规监管模式。 相似文献
148.
Xiaojie Xu 《Journal of applied statistics》2018,45(13):2455-2480
This study investigates causal structure among daily Chicago Board of Trade corn futures prices and seven regional cash series from Iowa, Illinois, Indiana, Ohio, Minnesota, Nebraska, and Kansas for January 2006–March 2011. Their wavelet transformed series are further analyzed for causal relationships at different time scales. Empirical results indicate no causality among states or between the futures and a cash series for time scales shorter than one month. As scales increase but do not exceed a year, bidirectional causal flows are determined among all prices. The information leadership role of the futures against a cash price is identified for the scale longer than one year and raw series, at which no interstate causality is found. 相似文献
149.
In late-phase confirmatory clinical trials in the oncology field, time-to-event (TTE) endpoints are commonly used as primary endpoints for establishing the efficacy of investigational therapies. Among these TTE endpoints, overall survival (OS) is always considered as the gold standard. However, OS data can take years to mature, and its use for measurement of efficacy can be confounded by the use of post-treatment rescue therapies or supportive care. Therefore, to accelerate the development process and better characterize the treatment effect of new investigational therapies, other TTE endpoints such as progression-free survival and event-free survival (EFS) are applied as primary efficacy endpoints in some confirmatory trials, either as a surrogate for OS or as a direct measure of clinical benefits. For evaluating novel treatments for acute myeloid leukemia, EFS has been gradually recognized as a direct measure of clinical benefits. However, the application of an EFS endpoint is still controversial mainly due to the debate surrounding definition of treatment failure (TF) events. In this article, we investigate the EFS endpoint with the most conservative definition for the timing of TF, which is Day 1 since randomization. Specifically, the corresponding non-proportional hazard pattern of the EFS endpoint is investigated with both analytical and numerical approaches. 相似文献
150.
China??s oldest old population is estimated to quadruple by 2050. Yet, poverty rate for the oldest old has been the highest among all age groups in China. This paper investigates the relationship between economic stress, quality of life, and mortality among the oldest-old in China. Both objective economic hardships and perceived economic strain are examined. We base our investigation on data drawn from the Chinese Longitudinal Healthy Longevity Survey conducted between 2000 and 2005. Our sample includes 10,972 men and women between the ages of 80 and 105 in 2000. The data show that about 16% of these oldest-old lived under economic stress in 2000. The risk factors that make one vulnerable to economic stress include age, being male, being widowed or never married, being a minority member, having no education, having no living children, and not having children as main source of income, and having no pension. Economic stress is negatively associated with indicators of quality of life, such as the quality of medical care and mental well-being. The poor quality of life contributes to the higher mortality rate for the oldest old who are under economic stress. Results also show that perceived economic strain increases the risk of mortality by 42% in rural areas, even after controlling for basic demographic characteristics, life style factors, and major health events.?For the rural oldest-old, having children as a main source of income and having access to pension alleviates the negative impact of economic hardship on mortality hazard by 23 and 66% respectively. However, in urban areas, economic stress has no direct impact on the hazard of mortality. 相似文献